I can see that if you felt your QA people had a history of intentionally favoring one vendor or another. I could actually see that happenning in certain countries and industries now that you point it out. It would be indicative of a very corrupt environment where bribes and kickbacks are a common feature in business. There are numerous places I could see that happen.
It's a shame really, that even quality control people would be susceptiable to that.
Craig